1. Field of the Invention
The invention relates to a fuel injector for internal combustion engines.
2. Description of Prior Art
DE 10 2004 005 452 A1 has disclosed a fuel injector with a directly actuatable injection valve element and a one-stage boosting of the actuator stroke by means of a pulling actuator for opening the nozzle needle. In it, an actuator-side coupler piston actuated by means of an actuator acts on a coupler chamber while a coupler piston connected to the nozzle needle acts on a control chamber. The coupler chamber and control chamber are hydraulically connected via a conduit. The conduit is let into an intermediate disk situated between the injector body and a nozzle body.
Powerful accelerations occur upon actuation of the actuator and corresponding oscillations of the actuator occur at the end of the actuator stroke, both of which are transmitted to the nozzle needle via the hydraulic chambers, causing the nozzle needle to resonate. These oscillations cause fluctuations in injection quantity since changes occur in the throttle cross section of the nozzle needle at the nozzle needle sealing seat.
The object of the present invention is to create a compactly designed fuel injector in which the transmission of the oscillations of the actuator stroke to the nozzle needle is suppressed while nevertheless retaining a rapid opening and closing of the nozzle needle.